Chuck for rock-drills.



No. 695,338. v Patented Manu', |902.`

n.11. HAMIL'L.

cuucxfqn nocx omLLs. l Dec. 1900.)

(Apphcatxon filed Wt'ic 655e@ `ffm/ern Cof bridge.

UNITED STATES PATENT OFFICE.

ROBERT H. HAMILL, OF SALMO, CANADA.

CHUCK FOR ROCK-VDRILLS.

SPECIFICATION forming part 0f Letters Patent No. 695,388, dated. March 11, 1902.'

Application filed December 4,1900. Serial No.' 38,656. (No model.) l

To all whom it mar/.concerns Be it known that I, ROBERT H. HAMILL, of the Yellowstone Mine, Salmo, British Columbia, Canada, have invented'certain newand useful Improvements inf Chucks for .Rock- Drills, of which the following is a specification.

The object of my invention is to devise a chuck for rock-drills which will hold the shank In the drawings like letters of reference in-..

dicate corresponding parts in the different iigures.

A is the head of the chuck, suitably bored' In the.

to receive the shank B of the drill. v side of the head is formed a rectangularslot C, having its sides tapered inwardly, 'asindil cated in Fig. 1. In this slot islocated the chuck-key D, shaped similarly to the slot; Its inner sideis curved tofit against the shank of the drill and its lower end is preferably beveled oft', as shown, to prevent it catching.

the end of the drill-shank when the latter is placed in position. The sides of the slot and chuck-key being beveled, as` described, the key is prevented from falling through the slot and is thus always retained in positionv whether the drill-shank is in place or not.

The bridge E is formed on the side of the head extending over-the slot C. `A recess is formed in the bridge to receive the Wedge F. The ends of the wedge are preferably provided With lugs a to prevent the'wedge being drawn out of the recess in the bridge. The upper side of the recess is formed by the dovetailed key G, fitted into a similar slot in the When it is desired to remove the Wedge,rthe dovetailed key is driven out and the recess in the bridge is thus enlarged suficiently to permit of the smaller end of the wed ge with its lug being withdrawn.

The chuck-key D is so proportioned that when a drill-shank-fis in position `its'upper ksurface projectsabove the outer surface of the head, so that bydriving in the Wedge the chuck-key is forced against the shank of the drill, thus holdingfit securely in position. When it is desiredto remove the drill-shank, the Wedge is loosened, when the shank may be readilydrawn out.`

It will be noticedthat'the key G is tapered slightly, asshown, in.. Fig. 3, so that when driven home it cannot be'shaken loose, but v must be knocked out with a hammer or other suitable tool. It will also be noticed that the key G takes up all the Wear caused by the wedge F and that'when worn it can easily be replaced. The parts are so proportioned that When the key Gr has been removed and the Wedge withdrawn the chuck-key D'may be removed through-the bridgel y What I claim as my invention is l. A drill-chuck comprising a head, bored to receive a drillshank and formed with a slot communicating with the bore, in combination with a chuck-key inserted in the said slot; a bridge crossing the slot and formed with a dovetail groove in its under side; a

dovetailed 'keyritted into the said groove; and a wedge adapted to engage the dovetailed key and -the chuck-key, substantially "as and for the purpose specified.

2. A drill-chuck comprising a head, bored to receive a drill-shank and formed with a slot communicating with the bore in combination with a chuck-key inserted in the said slot; a bridge crossing the slot and formed with a dovetail tapered groove in its under side; a tapered dovetail key fitted into the said groove; anda wedge adapted toengage the dovetailed keyand the chuck-key, substantially as and for the purpose specitied.

3. A drill-chuck comprising a head, bored to receive a drill-shank and formed with an inwardly-tapering slot communicating with the bore, in combination with a similarlytapered chuck-key insertedin the said recess; a bridge crossing the slot and formed with a dovetail groove in its under side; a dovetail key fitted into the said groove; and

a wedge adapted to engage the dovetailed key IOO 4. A drill-chuck comprising a head, bored said groove and a wedge adapted to engage to receive a drill-shank and formed with an the dovetailed key and the chuck-key, sub 1o inwardly-tapering slot communicating with stantally as and for the purpose specified.

the bore, in combination with a similmly- Salmo, British Columbia, November, 1900.` 5 tapered chuck-key inserted in the said rel ROBERT I-I. HAMILL.

cess; a bridge crossing the slot. and formed In presence ofwitah a dovemil tapered groove in its under H. E. T. HAMILTON,

side; a tapered dovetail key fitted into lche XV. F. HAMILTON. 

